张先龙 戴克戎 汤亭亭 张先龙(上海市第六人民医院骨科)；戴克戎(上海第二医科大学附属第九人民医院)；汤亭亭(上海第二医科大学附属第九人民医院) 骨与关节损伤杂志 2000 0 15 1


    关键词：接骨板；骨折愈合；应力遮挡；生物力学 期刊 gygjsszz 0 30??32 论著 fur -->


    

摘 要：目的 明确应力松弛接骨板体内应力遮挡率变化及其对骨折愈合力学性能的影响。方法 将兔两侧胫骨干横形截骨后,分别以应力松弛接骨板(Stress-relaxation plate SRP)和传统坚硬接骨板(Rigid plate RP)固定,观察其应力遮挡率变化及愈合骨力学性能变化。结果 两组固定初期,应力遮挡率均在70%左右,此后,SRP组随着固定时间延长,应力遮挡率逐渐下降,8周后,明显低于RP组;与此相应,愈合骨力学性能也逐渐增加,至48周达到正常骨的93.63%。RP组,24周后愈合骨力学强度逐渐下降,48周时,最大三点弯曲强度仅为正常57.95%。结论 应力松弛接骨板体内应力遮挡率的下降与固定时间具有良好的相关性;应力遮挡作用的减弱,促进了愈合骨力学性能的恢复。

A Biomechanical Study of the Effects of Stress-relaxation Bone Plate on Fracture Healing

Zhang Xianlong,Dai Kerong,Tang Tingting

    (Department of Orthopaedics,The Ninth People's Hospital,Shanghai the Second Medical University,Shanghai,200011)

Abstract：Objective To study the changing rule of stress shielding rate of stress-relaxation plate SRP in Vivo,and its effects on the mechanical property of fracture healing.Methods The bilateral tibia of New Zealand rabbit were osteotomized and fixed with Stress-relaxation plate (SRP) and Rigid plate (RP)respectively.The stress shielding rate assay and ultimate bending strength test (UBS) were used in this experiment from 2 to 48 weeks postoperatively.Results The stress shielding rate of either fixing with SRP or RP was about 70% at the beginning of fixation,but the stress-shielding rate of SRP decreased gradually along with the prolongation of fixing time.By 8 to 48 weeks after fixation,it was significantly lower than that of RP(P<0.05～0.01),and stabilized at about 27% during 36～48weeks after fixation.Meanwhile,The mechanical strength of united bone restored gradually,the UBS was 93.63 percent of the normal rabbit's tibia by 48 weeks.On the contrary,The mechanical property of synthetic bone reduced gradually along with the prolongation of fixation time,The UBS was only 57.95 percent of the normal rabbit's tibia by 48 weeks.Conclusions The SRP can gradually lower down its stress shielding rate in Vivo,so as to enhance the recovery of mechanical property of synthetic bone.

    Key words ： Bone plate;Fracture healing;Stress shielding;Biomechanics▲

坚硬接骨板如AO加压接骨板,于其强大应力遮挡作用,造成固定骨段骨质疏松,骨折愈合异常,愈合强度低等不足而难以提供骨折愈合所需的理想力学环境 ......